Porcupine Programmer

Programming rants, random stuff and some more programming.

setHasOptionsMenu Gotcha

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When your Fragment puts some actions in the action bar, it should call setHasOptionsMenu(true). And where should you make this call? You probably follow samples and call it from onCreate() callback.

Later you decide to hide one of the actions under certain circumstances. The way do to this is to implement onPrepareOptionsMenu(Menu) callback and alter the Menu object passed as an argument.

If you are not careful, depending on the visibility precondition you apply, you might have implemented instant crash on OS versions before Jelly Bean. On API level 17, the onPrepareOptionsMenu is called from runnable posted on some handler; on older versions the menu callbacks are called synchronously, so they are really called from onCreate(), which means that your Fragment is not yet fully initialized.

What’s the takeaway? Always test your app on wide variety of devices and OSes before the release, do not trust official Android samples, and call setHasOptionsMenu(true) at the end of onActivityCreated().